"' 


IMAGE  EVALUATION 
TEST  TARGET  (MT-3) 


// 


y. 


(A 


1.0   lifia  iiiiiM 


I.I 


11.25 


!ff  i^    12.2 


a 


2.0 


1.8 


M.  mil  1.6 


V] 


<^ 


/i 


v: 


% 


gb 


iV 


iV 


:\ 


\ 


^9> 


^\/#^\ 


"' 


CIHM/ICMH 

Microfiche 

Series. 


CIHM/ICMH 
Collection  de 
microfiches. 


Canadian  Institute  for  Historical  Microreproductions  Institut  Canadian  de  microroproductions  historiques 

1980 


Technical  Notes  /  Notes  techniques 


The  Institute  has  attempted  to  obtain  the  best 
original  copy  available  for  filming.  Physical 
features  of  this  copy  which  may  alter  any  of  the 
images  in  the  reproduction  are  checked  below. 


Q 


Coloured  covers/ 
Couvertures  de  couleur 


L'Institut  a  microfilm^  le  meilleur  exemplaire 
qu'il  lui  a  6t6  possible  de  se  procurer.  Certains 
d6fauts  susceptibles  de  nuire  A  la  qualitd  de  la 
reproduction  sont  not6s  ci-dessous. 


D 


Coloured  pages/ 
Pages  de  couleur 


The 
poa 
oft 
filnr 


The 
con 
or  t 
app 


D 
D 
D 


Coloured  maps/ 

Cartes  gdographiques  en  couleur 


Pages  discoloured,  stained  or  foxed/ 
Pages  d6culor6es,  tachetdes  ou  piqu6es 


Tight  binding  (may  cause  shadows  or 
distortion  along  interior  margin)/ 
Reliure  serr6  (peut  causer  de  I'ombre  ou 
de  la  distortion  le  long  de  la  marge 
int6rieure) 


D 
D 


D 


Coloured  plates/ 
Planches  en  couleur 


Show  through/ 
Transparence 


Pages  damaged/ 
Pages  endommag6es 


The 
filnn 
inst 


Mai 
in  0 
upp 
boti 
foll< 


D 


Additional  comments/ 
Commentaires  suppldmentaires 


Bibliographic  Notes  /  Notes  bibliographiques 


D 
D 
D 
D 


Only  edition  available/ 
Seule  Edition  disponible 


Bound  with  other  material/ 
Relid  avec  d'autres  documents 


Cover  title  missing/ 

Le  titre  de  couverture  manque 


Plates  missing/ 

Des  planches  manquent 


n 


Pagination  incorrect/ 
Erreurs  de  pagination 


Pages  missing/ 

Des  pages  manquent 


Maps  missing/ 

Des  cartes  g6ographiques  manquent 


D 


Additional  comments/ 
Commentaires  suppl6mentaires 


The  images  appearing  here  are  the  best  quality 
possible  considering  the  condition  and  legibility 
of  the  original  copy  and  in  keeping  with  the 
filming  contract  specifications. 


The  last  recorded  frame  on  each  microfiche  shall 
contain  the  symbol  ^»>  (meaning  CONTINUED"), 
or  the  symbol  V  (meaning  "END"),  whichever 
applies. 


Les  images  suivantes  ont  6x6  reproduites  avec  ie 
plus  grand  soin,  compte  tenu  de  la  condition  et 
de  la  nettet6  de  I'exemplaire  filh-.6,  et  en 
conformity  avec  les  conditions  du  contrat  de 
filmage. 

Un  des  symboles  suivants  apparaftra  sur  la  der- 
nidre  image  de  cheque  microfiche,  selon  Ie  cas: 
Ie  symbole  — »>  signifle  "A  SUIVRE",  Ie  symbole 
V  signifie  "FIN". 


The  original  copy  was  borrowed  from,  and 
filmed  with,  the  kind  consent  of  the  following 
institution: 

National  Library  of  Canada 


L'exemplaire  filmd  fut  reproduit  grdce  d  la 
gdndrositd  de  I'dtablissement  prdteur 
suivant  : 

Bibliothdque  nationale  du  Canada 


Maps  or  plates  too  large  to  be  entirely  included 
in  one  exposure  are  filmed  beginning  in  the 
upper  loft  hand  corner,  left  to  right  and  top  to 
bottom,  as  many  frames  as  required.  The 
following  diagrams  illustrate  the  method: 


Les  cartes  ou  les  planches  trop  grandes  pour  dtre 
reproduites  en  un  seul  clich6  sont  filmdes  d 
partir  de  Tangle  supdrieure  gauche,  de  gauche  i 
droite  et  de  haut  en  bas,  en  prenant  Ie  nombre 
d'images  ndcessaire.  Le  diagramme  suivant 
illustre  la  mdthode  : 


1 

t 

3 

1 

a 

.    t    '. 

4 

5 

6 

-m* 


THE     HISTORY 


OV 


THE   NIAGARA  RIVER, 


By    G.    K.    GILBERT. 


Extracted  from  the  Sixth  Annual  Report  of  the  Commissioners  op 
THE  State  Reservation  at  Niagara,  for  the  Year  1889. 


►  ♦♦♦  ^- 


ALBAJHT: 

JA'IES    B.    LYON,    PRINTER. 

1890. 


. 


\  i 


c 


■7 

0 


-,  ^ 


^ 


1'  H  E     HISTORY 


OF 


, 


THE    NIAGARA   RIVER, 


By    (i.    K.    G  I  L  BERT. 


i;.\ii;\(ii;i)    I'ltiiM    iiii.;  Sixiii     \NN'i'\r,   IiKI'out  ov  niii  ('((Mmissidnkus  ok 

TlIK  STATK    ltK!<i;UVATl()N    AT   MlAiiAliA,    I'OK  TIIH    YkAU   IHHK. 


IV' , 


ALBANY : 

JAME.S    13.    LYON,    Till  NT  ER. 

18D0. 


r 


PLATE  I.—  Blrtl's-ejre  view  of  Niagara  river. 


Till-  HISTORY  OF  TIIH  NIAGARA  RIVER.' 


By  G.  K.  OiLiiKUT. 


The  Niii^uru  river  flows  from  Lake  Erie  to  Lake  Ontario.  The 
slioie  of  Eiie  is  more  than  MOO  feet  higher  than  tlie  shore  of 
Ontaiio;  but  if  you  pass  from  the  hij^her  shore  to  the  h)wor,  you 
do  not  (leieeud  at  a  uniform  rate.  Starting  from  Lake  Erie  and 
}i;()iii<T  northward,  you  travel  upon  a  phiiu  —  not  level  but  with  only 
gentle  undulations  —  until  you  approach  the  ahf)re  of  Lake  Ontario, 
and  then  suddenly  you  find  yourscdf  on  the  brink  of  a  high  blull* 
or  c'litt"  ov(U'looking  the  lower  lake,  and  separated  from  it  oidy  by 
a  narrow  sti'i])  of  sloping  ])lain.  The  birds-eye  view  in  Plate  I  is 
constructed  to  show  the  relations  of  these  various  features,  the 
two  lakes,  the  broad  plateau  lying  a  little  higher  than  the  shore  of 
Lake  Erie,  the  clirt",  which  geologists  call  the  Niagara  Escarpment, 
and  the  narrow  plain  at  its  foot. 

Where  the  Niagara  river  leaves  Lake  Erie  at  Buffalo  and  enters 
tlie  plain,  a  low  ridge  of  rock  crosses  its  path,  and  in  traversing 
this  its  water  is  troubled ;  but  it  soon  becomes  smooth,  spreads 
out  broadly,  and  indolently  loiters  on  the  plain.  For  three-fourths 
of  the  distance  it  can  not  be  said  to  have  a  valley,  it  rests  upon 
the  surface  of  the  plateau  ;  but  then  its  habit  suddenly  changes. 
By  the  short  rapid  at  Goat  Island  and  by  the  cataract  itself  the 
water  of  the  river  is  dropped  200  feet  down  into  the  plain,  and 
thence  to  the  clifl'  at  Lewiston  it  races  headlong  through  a  dt^ep 
and  narrow  gorge.  From  Lewiston  to  Lake  Ontario  there  are  no 
rapids.  The  river  is  again  broad,  and  its  channel  is  scored  so 
deeply  in  thci  littoral  plain  that  the  current  is  relatively  slow,  and 
the  level  of  its  water  surface  varies  but  slightly  from  that  of 
the  lake. 

The  narrow  gorge  that  contains  the  river  from  the  Falls  to 
Lewiston  is  a  most  peculiar  and  noteworth}^  feature.     Its  width 


I  This  ehsay  contains  the  substance  of  a  lecture  read  to  the  American  Association  for 
the  Advancement  of  Scieneo  iit  its  Toronto  meetinB,  Aususit,  1889. 


62  SixTfi  Annuai.  Rki'out  of  the 

rarely  0(,u!i1h  tlic  fourth  of  u  mile,  .iiul  its  (l(>|)tli  to  tlir  bottom  of 
the  river  niuf^es  from  '200  to  fiOO  ft-ct.  Its  wiills  are  so  steep  that 
opportunities  for  cliinliin;^  up  uud  down  tliem  are  rare,  ami  in 
these  walla  one  may  see  the  geologic  strueturo  of  the  plateau. 
They  are  eonstitnted  of  Ixnlded  roeks — limestone,  shale  and  sand- 
stone—  lyiiiK  nearly  horizontal,  and  a  little  (ixamination  shows 
that  the  samii  strata  occur  in  the  same  order  on  both  sides.  So 
evenly  are  they  matched,  and  so  uniform  is  tlu^  {general  width  of 
the  f^orj^e,  that  one  might  suspec^t,  after  a  hasty  examination,  the 
two  sides  had  been  cleft  asund»M'  by  some  PUitonic  agency.  But 
those  who  havi^  made  ;i  study  of  the  subjcuit  havi  eachcd  a  dif- 
ferent and  bett(!r  conclusion  —  the  conclusion  that  tlie  trench  was 
exeavatcul  by  running  water,  so  that  the  strata  of  the  two  sides 
are  alike  because  they  are  parts  of  continuous  sheets,  from  each 
of  which  a  narrow  strip  has  hen*  been  cut. 

The  (!outour  of  the  cataract  is  subject  to  change.  From  time  to 
time  blocks  of  rock  break  away,  falling  into  the  pool  below,  and 
new  shapes  are  then  given  totlm  brink  over  which  the  water  leaps. 
Many  such  falls  of  rock  have  taken  plac  since  the  white  man 
occupied  the  banks  nf  the  river,  and  the  l)reakiug  away  of  a  very 
large  section  is  still  a  recent  event.  By  such  (d)servation  wo  are 
assured  that  the  extent  of  the  gorge  is  increasing  at  its  end,  that 
it  is  growing  longer,  and  that  the  cataract  is  the  cause  of  its 
extension. 

This  determination  is  th(^  first  element  in  the  history  of  the  river. 
A  change!  is  in  progress  before  our  eyes.  Th(>  river's  history,  like 
htiman  history,  is  Ix'ing  enacted,  and  from  that  whicli  occurs  we 
can  draw  inferences  concerning  what  lias  occnri'cd  and  what  will 
occur.  We  can  look  forward  to  the  time  when  the  gorge  now 
traversing  the  fourth  })art  of  the  width  of  the  plateau  will  com- 
pletely divide  it,  so  that  the  Niagara  will  drain  Lake  Erie  to  the 
bottom.  We  can  look  back  to  the  time  when  there  was  no  gorge, 
but  when  the  water  flowed  on  the  top  of  the  plain  to  its  edge,  and 
the  Falls  of  Niagara  were  at  Lewistowu. 

We  may  think  of  the  river  as  laboring  at  a  task  —  the  task  of 
sawing  in  two  tin'  plateaii.  The  task  is  partly  accomplished. 
When  it  is  done  the  river  will  assume  some  other  task.  Before  it 
was  begun  what  did  the  river  do  ? 


• 


t 


COMMIHHIONKKH   01"   TFFK   STATE    RehEKVATION   AT   NlAQAIlA.        fiS 


4 


t 


How  can  wo  answer  tliis  (lUcstionV  Tin-  surplus  water  ilis- 
cliarj^ed  from  Lake  Erie  can  not  have  flowed  by  tliis  course  to  Lake 
Ontario  without  sawing  at  the  j)latfau.  IJefore  it  Ix^^an  the  cni- 
tinj^  of  thej^'or^e  it  (litl  not  flow  alonj^  this  line.  It  may  have  flowed 
somewhere  else,  hut  if  so  it  did  not  constitute  the  Niagara  river. 
The  commencement  of  the  cutting  of  tin*  Niagara  gorge  is  the 
beginning  of  the  history  of  the  Niagara  river.  We  have  accom- 
plisln'd  somewhat  of  our  jjurposo  if  we  have  discovered  that  our 
river  Inid  a  begiiniing. 

We  are  so  accustonKul  to  think  of  streams,  and  especially  large 
streams,  as  pernnment,  as  flowing  on  forever,  that  the  discovery 
of  a  definite;  beginning  to  the  life  of  a  great  river  like  the  Niagara 
is  important  and  impressive.  Hut  that  discovery  does  not  stand 
alone.  Indeed,  it  is  but  one  of  a  large  class  of  similar  facts 
familiar  to  students  of  geology.  Let  us  consider  for  a  moment 
the  ten«leucy  of  stream  histories  and  the  tendency  of  lake  histories. 
Wherever  streams  fall  ovcm-  rocky  ledges  in  ra])ids  or  in  cataracts, 
their  ])ower  of  erosion  is  greatly  increased  by  i\w.  rapid  descent, 
and  they  (h'epen  their  channels.  If  this  process  continues  long 
enough,  tin;  result  must  be  that  each  sti'eam  will  degrade  its 
channel  through  the  hard  ledges  until  the  descent  is  no  more  rapid 
there  than  in  other  parts  of  its  course.  It  follows  that  a  stream 
with  cascades  and  water-falls  and  numerous  rapids  is  laboring  at 
an  unfinislKHl  task.  It  is  either  a  young  stream,  or  else  nature 
has  recently  put  obstructions  in  its  path. 

Again,  consider  what  occurs  where  a  lake  interru])ts  the 
course  of  a  stream.  The  lower  part  of  the  stream,  the  outflow- 
ing part,  by  deepening  its  channel  continually  tends  to  drain 
the  lake.  The  u])per  course,  the  inflowing  stream,  brings  mud 
and  sand  with  it  and  deposits  them  in  the  still  water  of  tlh  lake, 
thus  tending  to  fill  its  basin.  Thus,  by  a  double  process,  the 
streams  are  laboring  to  extinguish  the  lakes  that  lie  in  their  way, 
and  given  sutHcient  time,  they  will  accomi)lish  this.  A  stream 
whose  course  is  interrujited  by  lakes  is  either  a  young  stream,  or 
else  nature  has  recently  put  obstructions  in  its  path. 

Now  if  you  will  study  a  large  map  of  North  America,  you  will 
find  that  the  region  of  the  Great  Lakes  is  likewise  a  region  of 
small  lakes.      A  multitude  of  lakes,  lakelets,  ponds  and  swamps 


■"■^r 


I 


64 


Sixth  Annual  Rkpout  ok  the 


where  ponds  once  were,  cliaracteriiie  tlio  surface  from  the  Great 
Lakes  northward  to  the  Arctic  ocean,  and  for  a  distance  southward 
into  the  Uniti^d  States.  In  tiie  same  rej^jion  water-falls  abound, 
and  many  streams  consist  of  mere  alternations  of  rapids  and 
pools.  Farther  south,  in  the  re<5ion  beyond  the  Ohio  river,  lakes 
and  cataracts  are  rare.  The  majority  of  the  streams  flow  from 
source  to  mouth  with  regulated  course,  their  waters  descending 
at  first  somewhat  steeply,  and  gradually  becoming  more  nearly 
level  as  they  proceed.  At  the  south  the  whole  drainage  system  is 
mature ;  at  tlie  north  it  is  innnatur<\  At  the  south  it  is  old ;  at 
the  north,  vouug. 

The  explanation  of  this  lies  in  a  great  geologic  event  of  some- 
what recent  date —  the  event  known  as  the  age  of  ice.  Previous 
to  the  ice  age  our  streams  may  have  been  as  tame  and  orderly  as 
those  of  the  Southern  States,  and  we  have  no  evidence  that  there 
were  lakes  in  this  region.  During  the  ice  age  the  region  of  the 
Great  Lakes  was  somewhat  in  the  condition  of  Greenland.  It  was 
covered  by  an  immeuse  sheet  of  ice  and  the  ice  was  in  motion.  In 
general  it  moved  from  north  to  south.  It  carried  with  it  whatever 
lay  loose  upon  the  surface.  It  did  more  than  this,  for  just  as  the 
soft  water  of  a  stream,  by  dragging  sand  and  pebbles  over  the 
bottom,  wears  its  channel  dee})er,  so  the  plastic  ice,  holding  grains 
of  sand  and  even  large  stones  in  its  under  surface,  dragged  these 
across  the  underlying  rock,  and  in  this  way  not  only  scoured  and 
scratched  it,  but  even  wore  it  away. 

In  yet  other  ways  the  moving  ice  mass  was  analagous  to  a  river. 
Its  motion  was  perpetual,  and  its  form  changed  little,  but  that 
which  moved  was  continually  renewed.  As  a  river  is  supplied  by 
rain,  so  the  glacier  was  supplied  by  snow  falling  upon  regions  far 
to  the  north.  To  a  certain  extent  the  glacier  discharged  to  the 
ocean  like  a  river,  breaking  up  into  icebergs  and  floating  away  ; 
but  its  chief  discharge  was  upon  the  land,  through  melting.  The 
climate  at  its  southern  margin  was  relatively  warm,  and  into  this 
warm  climate  the  sheet  of  ice  steadily  Dushed  and  w.as  as  steadily 
dissolved. 

Whatever  stones  and  earth  were  picked  up  or  torn  up  by  the  ice, 
moved  with  it  to  its  southern  margin  and  fell  to  the  ground  as  the 
ice  melted.     If  the  position  of  the  ice  margin  had  been  perfectly 


•i 


Commissioners  of  the  State  Eeservation  at  Niagara.      65 


•Jl 


uniform,  its  contiauously  deposited  load  might  have  built  a  single 
high  wall ;  but  as  the  seasons  were  cold  or  warm,  wet  or  diy,  the 
ice  margin  advanc(Hl  and  retreated  with  endless  variation,  iud  this 
led  to  the  deposition  of  irregular  congeries  of  hills,  constitutiug 
what  is  known  as  the  "  drift  deposit."  Eventually  the  warm 
climate  of  the  south  prevailed  over  the  invader  born  of  a  cold 
climate,  compelling  it  to  retreat.  The  motion  of  the  ice  current 
was  not  reversed,  but  the  front  of  the  glacier  was  melted  more 
rapidly  than  it  could  be  renewed,  and  thus  its  area  was  gradually 
restricted.  During  the  whole  period  of  retrenchment,  the  deposi- 
tion of  drift  proceeded  at  the  margin  of  the  ice,  so  that  the  entire 
area  that  it  formerly  occupied  is  now  diversified  by  irregular  sheets 
and  heapings  of  earth  and  stone. 

The  ancient  configuration  of  the  country  was  more  or  less 
modified  by  the  erosive  action  of  the  ice,  and  it  was  further  modi- 
fied by  the  deposits  of  drift.  The  destructive  and  constructive 
agencies  together  gave  to  the  land  an  entirely  new  system  of  hills 
and  valleys.  When  the  ice  was  gone,  the  rain  that  fell  on  the  land 
could  no  longer  follow  the  old  lines  of  drainage.  Some  of  the  old 
valleys  had  perhaps  been  obliterated ;  others  had  been  changed 
so  that  their  descent  was  in  a  different  direction ;  and  all  were 
obstructed  here  and  there  by  the  heaps  of  drift.  The  waters  weie 
held  upon  the  surface  in  innumerable  lakes,  each  overflowing  at 
the  lowest  side  of  its  basin,  and  thus  giving  birth  to  a  stream  that 
descended  to  some  other  lake.  Often  the  new  lines  of  descent  — 
the  new  water  courses  —  crossed  regions  that  before  had  had  no 
streams,  and  then  they  were  compelled  to  dig  their  own  channels. 
Thus  it  was  that  the  whole  water  system  of  a  vast  region  was 
refashioned,  and  thus  it  has  come  to  pass  that  the  streams  of  this 
region  are  young. 

Like  every  other  stream  of  the  district  of  the  Great  Lakes,  the 
Niagara  was  born  during  the  melting  of  the  ice,  and  so  we  may 
begin  our  chronicle  with  the  very  beginning  of  the  river. 

If  you  will  again  call  to  mind  the  features  of  a  general  map  of 
the  United  States  and  Canada,  and  consider  the  direction  in  which 
the  streams  flow,  you  will  perceive  that  there  is  a  continuous 
upland,  a  sort  of  main  divide,  separating  the  basin  of  the  Great 
Lakes  from  the  basin  of  the  Mississippi.     (A  part  of  its  course 


< 


66 


Sixth  Annual  Report  of  the 


appears  as  a  broken  line  on  the  maps  in  Plates  IV  and  V.)  It  is  not 
a  mountain  range.  In  great  pjirt  it  is  a  region  of  lulls.  In  places 
it  is  only  the  highest  part  of  the  plain.  But  it  is  nevertheless  a 
continuous  upland,  else  the  waters  would  not  be  parted  along  its 
course.  When  the  ice  had  its  greatest  extent,  it  passed  over  this 
upland,  so  that  the  waters  produced  by  its  melting  fell  into  the 
Ohio  and  other  tributaries  of  the  Mississippi,  as  well  as  into 
streams  that  discharged  to  Delaware  and  Chesapeake  bays.  After- 
ward, when  the  glacier  gradually  fell  back,  there  came  a  time 
when  the  ice  front  lay  in  the  main  to  the  north  of  the  great  water- 
parting,  but  had  not  yet  receded  from  the  Adirondack  mountains, 
so  that  the  water  that  flowed  from  the  melting  glacier  could  not 
escape  by  way  of  the  St.  Lawrence  river,  but  gathered  as  a  lake 
between  the  upland  divide  and  the  ice  front.  In  fact  it  formed 
not  one  but  many  lakes,  each  discharging  across  the  divide  by 
some  low  pass ;  and  as  the  great  retreat  progressed,  these  lakes 
were  varied  in  number  and  extent,  so  that  their  full  history  is 
exceedingly  complex. 

The  surfaces  of  these  lakes  were  stirred  by  the  winds,  and  waves 
beat  upon  their  shores.  In  places  they  washed  out  the  soft  drift 
and  carved  cliffs ;  elsewhere  they  fashioned  spits  and  bars.  These 
cliffs  and  spits  and  other  monuments  of  wave  work  survive  to  the 
present  time,  and  have  made  it  possible  to  trace  out  and  map 
certain  of  the  ancient  lakes.  The  work  of  surveying  them  is 
barely  begun,  but  from  what  is  known  we  may  add  a  chapter  to 
the  history  of  our  river. 

There  was  a  time  when  one  of  these  lakes  occupied  the  western 
portion  of  the  basin  of  Lake  Erie,  and  discharged  across  the 
divide  at  the  point  where  the  city  of  Fort  Wayne  now  stands, 
running  into  the  Wabash  river  and  thence  into  the  Ohio.  The 
channel  of  this  discharge  is  so  well  preserved  that  its  meaning  can 
not  be  mistaken,  and  the  associated  shore- lines  have  been  traced 
for  many  miles  eastward  into  titef  Ohio,  and  northward  into 
Michigan.  Afterward,  this  lake  found  some  other  point  of  dis- 
charge, and  a  new  shore-line  was  made  twenty-five  feet  lower. 
Twice  again  the  point  of  discharge  was  shifted,  and  other  shore- 
lines were  formed.  The  last  and  lowest  of  the  series  has  been 
traced  eastward  across  the  States  of  Ohio  and  Pennsylvania  and 
into  western  New  York,  where  it  fades  away  in  the  vicinity  of  the 


COMMISaiONERS   OF   THE   StATE   RESERVATION   AT  NIAGARA.         67 


town  of  Carfyville.  At  each  of  the  stages  represented  by  these 
four  shore-lines,  tlie  site  of  the  Niagara  Avas  either  buritd  beneath 
the  ice  or  else  submerged  under  the  lake  bordering  the  ice.  There 
was  no  river. 

The  next  change  in  the  history  of  the  lakes  was  a  great  one. 
The  ice,  which  had  previously  occupied  nearly  the  whole  of  the 
Ontario  basin,  so  far  withdrew  as  to  enable  the  accumulated  water 
to  ilow  out  by  way  of  the  Mohawk  valley.  The  level  of  discharge 
was  thus  suddenly  lowered  550  feet,  and  a  large  district  previously 
submerged  became  dry  land.  Then  for  the  first  time  Lake  Erie 
and  Lake  Ontario  were  separated,  and  then  for  the  first  time  the 
Niagara  river  carried  the  surplus  water  of  Lake  Erie  to  Lake 
Ontario. 

The  waves  of  the  new-born  Lake  Ontario  at  once  began  to  carve 
about  its  margin  a  record  of  its  existence.  That  record  is  wonder- 
fully clear,  and  the  special  training  of  the  geologist  has  not  been 
necessary  to  the  recognition  of  its  import.  The  earliest  books  of 
travel  in  western  New  York  describe  the  Ridge  road,  and  tell  us 
that  the  ridge  of  sand  and  gravel  which  it  follows  was  even  then 
ogiii/(Hl  by  all  residents  as  an  ancient  beach  of  the  lake.'  In 
the  Province  of  Ontario  th(^  beach  was  examined  and  described  by 
the  groat  English  geologist,  Charles  Lyell,  during  his  celebrated 
journey  in  America,'-  and  it  afterward  received  more  careful  study 
by  Mr.  Sandford  Fleming,-*  and  by  the  geologists  of  the  Canadian 
Sarv(\y. '  In  western  New  Yf)rk  it  was  traced  otit  by  the  great 
American  geologist,  James  Hall,  during  his  survey  of  the  geology 
of  the  fourth  district  of  the  State.''  Within  a  few  years  more 
attention  has  been  given  to  detail.  Professor  J.  W.  Spencer  has 
traced  the  line  continuously  from  the  head  of  the  lake  at  Hamilton 
])ast  Toronto,  Windsor  and  Grafton  to  the  vicinity  of  Bellevdle," 


1  (!.  Scliultz,  Jr.:  Triivcls  on  an  inlfind  voyago  *  *  *  jn  the  years  1807  and  1808, 
Xcw  York  IHin,  p.  hi>. 

I)e  Wilt  ('Hilton:  Discourwo  boforo  tlw-J»«\v  V(jrk  Iliatorieal  Sucioty,  IHII,  p.  OS. 

Fnuiris  Hall:  Travols  in  Canada  and  the  United  StatdB  in  IHIO  and  1817,  Bo:-(ton,  IhiH, 
p  nil. 

•2  Tivn-fis  in  N'ortli  .Vniorifa  in  tlii«  your.s  lH\i->.    Now  York.  Ihi.';.    Vol.  2,  pp.  8(1-87. 

:i  Sanill'oi'd  FkMiiini;:  N'otus  on  tlui  Davoiiport  trravcl  drift.  Cuiiiidian  Journal,  Now 
Sorii'fi,  vol.  f>.  PI  I.  '.U.-'J."):i. 

4  Oeolowifal  Survoy  of  (Janada,  roportto  inn:),  pp.  9H-'.tir). 

n  Natural  History  of  Now  York.    Ooolouy.  Tart  IV.  pp.  ;i4«  r.t. 

('.  (Jonnnuiiicatcd  to  the  Philosophical  Sooioty  of  Washington ;  to  l)o  puhlishod  in 
Vol.  11  of  tlu>  liullctin  of  the  Socioty. 


™HC- 


68 


Sixth  Annual  Report  op  the 


beyond  which  point  it  is  hard  to  follow.  Soutli  of  the  lake,  I 
myself  have  traced  it  from  Hamilton  to  (^ueeuston  and  Lewiston ; 
thence  to  Rochester,  and  all  abont  the  eastern  end  of  the  basin  to 
Watertown,  beyond  which  point  it  is  again  difficult  to  trace. 
Southeast  of  the  present  margin  of  Lake  Ontario,  there  was  a 
great  bay,  extending  as  far  south  as  Cayuga  lake,  pnd  including 
the  basil;  of  On(!ida  lake,  and  it  was  from  this  bay  that  the  dis- 
charge took  place,  the  precise  point  of  overflow  being  tin  present 
site  of  the  city  of  Rome.  )r  this  predecessor  of  Lake  Ontario 
Professor  Spencer  has  j^roposed  the  name  of  Iroquois. 

Putting  together  the  results  of  his  survey  and  of  my  own,  I 
have  been  able  to  prepare  a  map  (PI.  II)  exhibiting  with  a  fair 
amount  of  detail  the  outline  of  the  old  lake.  It  will  be  observed 
that  the  northeastern  portion  of  the  shore  is  not  traced  out.  In 
fact  it  is  not  traceable.  The  water  w•^s  contained  on  that  side  by 
the  margin  of  the  glacier,  and  with  the  final  melting  of  the  ice  all 
record  of  its  shore  vanished. 

The  form  and  extent  of  Lake  Iro(]uois,  and  the  form  and  extent 
of  each  other  lake  that  bordered  the  ice  front,  were  determined 
partly  by  the  position  of  the  pass  over  which  the  discharge  took 
place  and  by  the  contour  of  the  land;  but  they  were  also  deter- 
mined to  a  great  extent  by  the  peculiar  attitude  of  the  laud. 

Perhaps  a  word  of  general  explanation  is  necessary  in  speaking 
of  the  attitude  of  the  laud.  Geologists  are  prone  to  talk  of  eleva 
tion  and  subsidence  —  of  the  uprising  of  the  earth's  crust  at  one 
place  or  at  one  time,  and  of  its  down-sinking  at  another  place  or 
another  time.  Their  language  usually  seems  to  imply  the  rise  or 
fall  of  an  area  all  together,  without  any  relative  displacement  of 
its  parts;  but  you  will  readily  see  that,  unless  a  rising  or  sinking 
tract  is  torn  asunder  from  its  surroundings,  there  must  be  all  about 
it  a  belt  in  which  the  surface  assumes  an  inclined  position,  or,  in 
other  words,  where  the  attitude  of  the  land  is  changed.  If  the 
district  whose  attitude  changes  is  a  lake  basin,  the  change  of  atti- 
tude Avill  cause  a  change  in  the  position  of  the  line  marked  about 
the  slopes  of  the  basin  by  the  water  margin,  and  it  may  even  cause 
the  overflow  of  the  basin  to  take  a  new  direction. 

The  Oiitai'io  basin  has  been  subjected  to  a  very  notable  change 
of  attitude,  and  the  effect  of  this  change  has  been  to  throw  the 


x> 

0; 

s 

ja 

I 

x 
(/. 

o 


i  S 

e    *- 
s    « 

5"    ^ 

g    ^ 

«■    — 

*     c 
«    ~ 

e 

?  1 
E  = 

I  ~t 

«     c 
B   "= 

h)   -a 
"    ea 

tif 

c 
u 
■o 
>< 


•a 


2 
o 

M 

H 


Commissioners  of  the  State  Reservation  at  Niagara.      69 


ancient  shore-line  out  of  level.  When  the  shore-line  was  wrought 
by  the  waves,  all  parts  of  it  must  have  lain  in  the  same  horizontal 
piano,  and  had  there  been  no  change  in  the  attitudt^  of  the  ba.siu, 
every  point  of  the  shore-line  would  now  be  found  at  the  level  of 
tiie  old  outlet  at  Rome.  Instead  of  this,  we  find  that  the  old 
gravel  spit  near  Toronto  —  tlie  Davenport  ridg(>  —  is  forry  feet 
higlier  than  the  coutemporaniM)us  gravel  spit  on  which  Lewiston 
is  built ;  at  Bell  nille,  Ontario,  the  old  shore  is  200  feet  higher 
than  at  Ilochester,  N.  Y.  ;  at  Watertown  800  feet  higher  than  at 
Syracuse ;  and  the  lowest  point,  in  Hamilton,  at  the  head  of  the 
lake,  is  iVliy  feet  lower  than  the  Jiighest  point  near  Watertown. 
From  these  and  other  measurements  we  le.aru  that  the  Ontario 
basin  with  its  new  attitude  inclines  more  to  the  south  and  west 
than  with  the  old  attitude. 

The  point  of  discharge  remained  at  Rome  as  long  as  the  ice  was 
crowded  high  against  the  northern  side  of  the  Adirondack 
mountains,  but  eventually  there  came  a  time  when  the  water 
escaped  eastward  between  the  ice  and  the  mountain  slope.  The 
line  of  the  St.  Lawrence  was  not  at  once  opened,  so  that  the  sub- 
sidence was  only  partial.  The  water  was  held  for  short  times  at 
various  intermediate  levels,  recorded  at  the  east  in  a  series  of  faint 
shore-lines.  Owing  to  the  attitutle  of  the  land,  these  shores  are 
not  traceable  all  about  the  basin,  but  pass  beneath  the  present 
water  level  at  various  points. 

Finally  the  ice  blockade  was  raised  in  the  St.  Lawrence  valley, 
and  the  ])resent  outlet  was  established.  During  the  period  of 
final  retreat  the  attitude  of  the  land  had  slowly  changed,  so  that  it 
wjiSj  not  then  so  greatly  depressed  at  the  north  as  before  ;  but  it 
had  not  yet  acquired  its  present  position,  and  for  a  time  Lake 
Ontario  was  smaller  than  now,  its  western  margin  lying  lower 
down  on  the  slope  of  the  basin. 

An  attempt  has  been  made  in  PI.  Ill  to  exhibit  diagramatically 
the  relations  of  ice  dams  and  basin  attitudes  to  one  another  and  to 
the  river.  The  various  elements  are  projected,  with  exaggeration 
of  heights,  on  a  vertical  plane  running  a  little  west  of  south,  or 
parallel  to  the  direction  of  greatest  inclination  of  old  water-planes. 
At  N  is  represented  the  Niagara  escarpment  and  the  associated 
slope  of  the  lake  basin  ;  at  A  the  Adirondack  mountains.     R  and 


70 


Sixth  Annuax,  Report  of  the 


T  are  the  passes  at  Rome  and  at  the  Thousand  Islands.  Succes- 
sive positions  of  tlio  ico  front  are  marked  at  I',  I-  and  I'.  The 
strai^h  lue  numbered  1  represfmtH  the  level  of  lake  water 
previous  to  the  origin  of  the  Niaj^ara  river;  2  gives  the  first 
position  of  the  water  level  jvfter  the  estal/lishment  of  the  Home 
outlet ;  and  the  level  graduall}'  shifted  to  3 ;  4  is  the  first  of  the 
series  of  teraporaiy  water  levels  when  the  water  escaped  between 
the  mountain  slojje  and  thci  ice  front ;  5  represents  the  first 
position  of  the  water  level  after  the  occupation  of  the  Thousand 
Island  outlet;  and  (5,  the  present  level  of  Lake  Ontario. 

It  should  b(^  addedparenthetically  that  the  shore  of  Lake  Iroquois 
as  mapped  in  PI.  II  is  not  quite  synchronous.  Between  2  and 
3  of  PI.  Ill  there  was  a  continuous  series  of  water  levels,  but  it 
was  not  easy  to  map  any  one  except  the  highest.  The  northern 
part  of  the  map  delineates  the  margin  of  water  level  2,  and  the 
southern  part  the  margin  of  water  level  3. 

It  is  easy  to  see  that  these  various  changes  contribute  to  modify 
the  history  of  the  Niagara  river.  In  the  beginning,  when  the 
cataract  was  at  Lewiston,  the  margin  of  Lake  Ontario,  instead  of 
being  seven  miles  away  as  now,  was  only  one  or  two  miles  distant, 
and  the  level  of  its  water  was  about  seventy-five  feet  higher  than 
at  present.  The  outlet  of  the  lake  was  at  Rome,  and  while  it  there 
continued,  there  was  a  progressive  change  in  the  attitude  of  the 
land,  causing  the  lake  to  rise  at  the  mouth  of  the  Niagara  until  it 
was  125  feet  higher  than  now.  It  fairly  washed  the  foot  of  the 
clitf  at  Queeuston  and  Lewiston.  Then  came  a  time  when  the 
lake  fell  suddenly  through  a  verticjd  distance  of  250  feet,  and  its 
shore  retreated  to  a  position  now  submerged.  Numerous  minor 
oscillations  were  caused  by  successive  shiftiugs  of  the  point  of 
discharge,  and  by  progressive  changes  in  the  attitude  of  the 
land,  until  finally  the  present  outlet  was  aci^uired,  at  which 
time  the  Niagara  river  had  its  greatest  length.  It  then  encroached 
five  miles  on  the  modern  domain  of  Lake  Ontario,  and  began  a 
delta  where  now  the  lead-line  runs  out  thirty  fathoms. 

While  the  level  of  discharge  was  lower  than  now,  the  river  had 
different  powers  as  an  erodin,  ..gent.  The  rocks  underlying  the 
low  plain  along  the  margin  of  the  lake  are  very  soft,  and  where  a 
river  flows  across  yielding  rocks,  the  depth  to  which  it  erodes  is 


1 

a 


COMMI88IONE11R  OF  Till".   S'lATE   RESERVATION   AT  NueAltA.         71 


limitod  chiefly  by  th(»  level  of  its  point  of  (liscluir^o.  So  when 
the  poiut  of  <lis(tluirfj;o  of  the  Nia^iira  river  —  the  surface  of  the 
lake  to  which  it  llowcd  —  was  from  100  to  200  feet  lowtn*  than  now, 
the  river  carved  a  channel  far  deeper  than  it  could  now  carve. 
Wiien  afterward  the  rise  of  land  in  the  vicinity  of  the  outhit 
carried  the  wat(U'  f^radiially  up  to  its  present  {)osition  in  the  basit 
this  channel  was  partly  lilled  by  sand  and  other  (h'bris  brou;^ht 
by  the  current;  bilt  it  was  not  completely  tilled,  and  its  n^mark- 
able  present  depth  is  one  of  the  survivinj^  witnesses  of  the  sliiftin<^ 
drama  of  the  Ontario.  Near  Fort  Niaj^ara  twelve  fathoms  of  water 
are  shown  on  the  charts. 

Mr.  Warren  UphiiUi  has  made  a  similar  discovery  in  the  basin 
of  the  Red  River  of  the  North.  That  basin  held  a  large  lake, 
draining  southward  to  the  Mississippi  —  a  lake  whose  association 
with  the  great  glacier  Upham  appropriately  signali/etl  by  naming 
it  after  the  apostle  of  "the  glacial  theory,"  Louis  Aggassiz.  The 
height  of  the  old  Agassi/  shore  has  been  carefully  measured  by 
Mr.  Upham,  through  long  distances,  ami  it  is  found  to  rise  contin- 
uously, though  not  cpiite  uniformly,  toward  the  north.  Similar 
discoveries  have  been  made  in  the  basins  of  Erie,  Huron  and 
Michigan,  and  the  phenomena  all  belong  approximately  to  the 
same  epoch.  So,  while  the  details  remain  to  be  worked  out,  the 
general  fact  is  already  estalilished  that  (hiring  the  epoch  of  the  ice 
retreat  the  great  plain  constituting  the  Laurtuitian  basin  was  more 
inclined  to  the  northward  than  at  present. 

It  was  shown,  first  in  the  case  of  Lake  Agassiz,  and  afterward, 
as  already  stated,  in  tlie  case  of  Lake  Ontario,  that  the  change 
from  the  old  attitude  of  the  land  tc  the  present  attitude  was  in 
progress  during  the  epoidi  of  the  ice  retreat.  The  land  was  grad- 
ually rising  to  the  north  or  northeast.  In  each  lake  basin  the 
water  either  retreated  from  its  northern  margin,  so  as  to  lay  bare 
more  land,  or  encroached  on  its  southern  margin,  or  else  both 
these  changes  occurred  together;  and  in  some  cases  Ave  have  reason 
to  bt^lieve  that  the  changes  were  so  extensive  that  the  outlets  of 
lakes  wer  ^  shifted  from  northerly  passes  tf)  inore  southerly  passes. 

To  illustrate  the  eflect  of  the;  earlier  system  of  land  slopes  upon 
the  distribution  of  water  in  the  region  of  the  Great  Lakes,  I  have 
constructed  ihe  map  in  PI.  IV.      It  does  not  postulate  the  system 


mmHm 


'mf^^Hmm 


1^5- 


72 


Sixth  Annual  Report  op  the 


of  lovols  most  {liv()r«,'ont  from  tlio  pr«\sont  syHtem,  but  a  Hysttim 
Miurli  an  may  havo  (ixistod  at  tho  i)()iiit  of  time  wlien  the  last 
glacial  ice  was  melted  from  the  region.  The  moihu-u  system  of  drain- 
ago  is  drawn  in  l)roken  lines;  the  hy|)oth<itic  system  in  full  lines, 
with  shading  for  the  lake  areas  ;  and  a  heavier  broken  line  towjird 
the  bottom  of  the  map  marks  the  position  of  the  present  water- 
parting  at  the  southern  edge  of  the  Laurentian  basin. 

lu  the  ancient  system  of  drainage,  Georgian  bay,  instead  of 
being  a  depeiiaeuc^y  of  Lake  Huron,  is  itself  the  principal  lake, 
and  receives  the  overflow  from  Huron.  It  expands  toward  the 
northeast  so  as  to  include  the  l)asiu  of  Lake  Nipissiug,  and  its 
discharge  is  across  a  somewhat  low  pass  at  the  east  end  of  Ldke 
Nipissing,  and  thence  down  the  Ottawa  river  to  the  St.  Lawrence. 
Lake  Michigan,  instead  of  communicating  with  Lake  Huron  by  a 
strait,  forms  a  tributary  lake,  discharging  its  surplus  through  a 
river.  Lake  Superior  has  the  sam  relations  as  now,  but  its  over- 
flow traverses  a  greater  distance  before  reaching  Lake  Huron. 
Superior,  Michigan,  Huron  and  Gecu'gia  constitute  a  lake  system 
by  themselves,  indei)endent  of  Erie  and  Ontario,  and  the  channel 
of  the  Detroit  river  is  dry.  Lake  Erie  and  Lake  Ontario,  both 
greatly  reduced  in  si/e,  constitute  another  chain,  but  their  con- 
necting link,  the  Niagara  river,  is  a  comparatively  small  stream, 
for  the  diversion  of  the  upper  lakes  robs  the  river  of  seven-eighths 
of  its  tributary  area. 

Whether  this  hypothetic  state  of  drainage  ever  existed,  whether 
the  ice  retreated  from  the  Nii)issing  ])ass  while  still  the  changing 
attitude  of  the  land  was  such  as  to  turn  the  Georgian  outlet  in  that 
direction,  are  questions  not  yet  answered.  But  such  data  as  I 
have  at  present  incline  me  to  the  belief  that  for  a  time  the  upper 
lakes  did  discharge  across  the  Nipissing  )iass. 

Professor  Spencer  jas  described  a  channel  by  which  Georgian 
bay  once  drained  across  a  more  southerly  pass  to  the  valley  of  the 
Trent  river,  and  thence  to  Lake  Ontario. '  He  states  that  there  is 
an  ancient  shore-line  about  Georgian  bay  associated  with  this 
outlet,  and  that  he  has  traced  this  line  westward  and  southward 
until  it  comes  down  to  the  shore  of  Lake  Huron,  demonstrating 
that  during  the  existence  of  that  outlet  also,  the  Detroit  river  ran 


1  Proc.  A.  A.  A.  S.,  37th  MeotinK  (Cleveland),  pp.  198-199. 


M 

»-*■ 

t^ 

a 

Tl 

a> 

|H 

f 

> 

> 

s 

p 

M 

n 

O 

"S? 


IB 


0 


a 

Tk 

«» 

<« 

a 

tr 

0 

T 

m 

p 

.- 

ts 

>« 

c 

3 

VI 

TT 

di 

B 

a 

V) 

f» 

a 

• 

» 

(S 

r 

0 

a 

'■^ 

^ 

p 

*4 

"! 

^ 

&- 

i,^ 

(X 

s 

» 

^ 

n 

p 

t 

a 

p* 

«^ 

■1 

•< 

ts 

c 

^ 

a 

»• 

J5 

V 

1 

-1 

■3 

5 

D* 

l: 

•< 

«* 

^, 

m* 

P 

3 

n 

0 

p- 

«*i 

r^ 

1 

w 

o 

» 

B 

"1 

, 

t 

c' 

» 

ct 

U) 

tn 

> 

SB 

g 

ftl 

•1 

p 

ct- 

? 

D. 

e 

-5 

s 

fB 

'-i 

UJ 

■* 

^> 

S" 

P 

■t 

,.,.^ — :~— -t!I,- »                   c--.. 

^•**'    -.-"*■■                           *'                          "^*--'*-                                t         *x 

V\., "  '^^^^^&7>-^  ^ 

i   '"'^^J^''''''^^^^^.^  "^ 

1                                           * '''^^^§w$$^y  f      ■    ^^ 

'                                                                                    *"?V^N^^  V                   ^ 

J                                                                            ^"'"""""^  \v§\            \               R^ 

0^' ■'                                                                      '*"•■""  V^^Jo  /           ^ 

(^  /                                                                                                    '^'^^^'^         l*^^^^ 

v                                                                  .'T>     ^^ 

"^  i                                                                                               /  J  I  -._<J' 

1.,     ,   ^     <N   ...  /MW' 

•           /"^>-.,  b                """X  ' ""'x^"'>^^T^  / 

,                          ,»  r"                 '"*^^^.2u                                                         ^^                 ^-"Tr^xN/     JCvnXxx^  '*'"'        ^ 

s*>           '•''■.       •'      'S*-,                    .-'       <^$y^  i^$$i$$/</     1^ 

i-^j-               ^\,'         \       '|S',f                  , -"■           ^>^$^^L/^^<v$oN-"'  'I       >• 

"--^.,.^'\                \                                       ^^'^l^^^i  1 

\    *    /v^<\ '                             rK\x\\\v^!^s^N!^s^ 

^.^7^'-<._  ^5                   ^^^^^^^»v 

"*' W  K  '^-       T-' 

V                           ''    '>-..-'^~<§T^                             \ 

'^■•••••^             •'*             *      ''*j'*\^                                    J 

\   'S           ^         \ 

1    .'  J                '^X            \ 

^■^         \ 

\     ,  -                   "^k         \ 

y\         ~%^  \ 

/            *\                      »\.  J 

' — ■ '. li _^_^ 

f'^'''  ' 

****""           "x^ 

■    1 

1 

X                                                                                                     ^^^>V^ 

1 

'■-- -r"^^^^: 

1 

i 

1 

■  — -^ 

'^i 

, 

/' 

K 

'  I      '^mmmmmmn 


"v'.f'  '"»im.f\,^ 


Commissioners  of  the  State  Reservation  at  Niagara.       73 


dry.  The  Trent  pass  is  much  higher  than  the  Nipissing  pass,  so 
that  it  appears  necessary  to  assume  that  during  the  history  of  the 
Trent  outlet  for  the  upper  lakes,  the  great  glacier  still  occupied 
the  region  of  Lake  Nipissing,  preventiag  the  escape  of  the  water 
in  that  direction. 

The  map  in  PI.  V  represents  the  system  of  lakes  and  outlets  at 
that  time.  It  is  largely  theoretic,  but  I  believe  its  general  features 
consistent   with    our   present   knowledge  of   the  facts. 

Unless  I  have  misunderstood  Professor  Spencer,  Lake  Ontario 
was  at  high  stage  in  the  first  part  of  the  epoch  of  the  Trent  valley 
outlet,  and  was  afterward  at  low  stage.  I  have  selected  as  the 
date  of  my  map  the  epoch  of  the  high  stage,  with  the  outlet  of 
Ontario  at  Rome,  and  have  indicated  an  ice  sheet  so  extensive  as 
to  block  the  way,  not  only  at  Lake  Nipissing,  but  at  the  pass  of  the 
Thousand  Islands.  The  d.ite  of  this  map  is  earlier  than  the  other; 
it  belongs  to  a  time  when  the  northward  depression  of  the  land  was 
greater.  Lake  Erie  is  represented  as  less  in  extent,  for  its  basin 
in  that  position  would  hold  less  water.  Huron  and  Ontario  would 
likewise  be  smaller  were  their  waters  free  to  escape  over  the  lowest 
passes ;  but  the  ice  blocks  the  way,  and  so  their  waters  are  raised 
to  the  level  of  higher  passes.  Of  the  contemporaneous  relations 
of  the  upper  lakes  we  know  nothing  at  present.  They  are  drawn 
as  though  commimicating  with  Lake  Huron,  but  it  is  ecjually  pos- 
sible that  they  fell  into  some  other  drainage  system.  Here  again 
the  Detroit  channel  was  not  in  use,  and  the  Niagara  river  was 
outlet  only  for  the  waters  of  the  Erie  basin. 

Graphic  methods  are  ill  adapted  to  the  communication  of 
qualified  or  indefinite  statements.  By  the  aid  of  a  map  one  can 
indicate  definitely  the  relation  of  Albany  to  other  j^laces  and  things, 
but  he  can  not  say  indefinitely  that  Albany  is  somewhere  in  eastern 
New  York,  nor  can  he  say,  with  qualification,  that  it  is  probably 
on  the  Mohawk  river.  For  this  reason  I  have  decided  to  i3ublish 
these  two  maps  only  after  hesitation,  l)ecause  I  should  greatly 
regret  to  produce  the  impression  that  the  particular  configuration 
of  lakes  and  outlets  here  delineated  has  been  actually  demon- 
strated. The  facts  now  at  command  are  suggestive  rather  than 
conclusive,  and  when  the  subject  shall  have  been  fully  investigated 
it  is  to  be  expected  that  the  maps  representing  these  epochs  will 


74 


Sixth  A>^nual  Report  of  the 


exhibit  uuiteriiil  differences  from  those  I  have  (Ir.iwii.  The  sole 
point  that  I  wish  to  deveh^p  at  this  time  is  the  jjrobability  tliat 
(birinj^  a  portion  of  the  history  of  the  Niagara  river,  its  drainage 
district — that  area  from  which  its  water  was  supplied  was  far 
less  than  it  is  at  the  present  time.  There  i  I'eason  to  believe  that 
during  an  epoch  which  may  have  been  short  or  long,  we  can  only 
vaguely  conjecture,  the  Niag-ira  was  a  comparatively  small  river. 

The  characters  of  the  goige  are  in  general  remarkably  nnifoi-m 
from  end  to  end.  Its  width  docs  not  vary  greatly ;  its  course  is 
flexed  but  slightly ;  its  Avails  exhibit  the  same  alternation  of  soft 
and  hard  rocks.  Lut  there  is  one  exceptional  point.  Midway, 
its  course  is  abruptly  bent  at  right  angles.  On  the  outside 
of  the  angle  there  is  an  enlargement  of  the  gorge,  and  this  enlarge- 
ment contains  a  deep  pool,  called  the  Whirlpool.  At  this  jjoint, 
and  on  this  side  only,  the  material  of  the  wall  has  an  exce])tional 
character.  At  every  other  point  there  is  an  alternation  of  shales, 
sandstones  and  limestones,  capped  above  by  an  unecpial  deposit 
of  drift.  At  this  point,  limestones,  sandstones  and  shales  disap})('ar, 
and  the  whole  wall  is  made  of  drift.  Here  is  a  place  where  the 
sti'ata  that  floor  the  plateau  ai'e  discontinuous,  and  must  have  been 
discontinuous  before  the  last  occupation  of  the  region  of  the  glacier, 
for  the  gap  is  filled  by  glacial  drift. 

Another  physiographic  feature  was  joined  to  this  by  Lyell  and 
Hall.  They  observed  that  the  cliff"  limiting  the  plateau  has,  in 
general,  a  very  straight  course,  with  few  indentations.  Bat  at  the 
town  of  St.  Davids,  a  few  miles  west  of  Queenston,  a  wide  flaring 
gap  occurs.  This  gap  is  partly  filled  by  drift,  and  although  the 
glacial  nature  of  the  drift  was  not  then  understood,  it  was  clearly 
perceived  by  those  geologists  that  the  drift-filled  break  marked 
the  position  of  a  line  of  erosion  established  before  the  ])eriod  of 
the  drift.  Putting  together  ihe  two  anomalies,  they  said  that  the 
drift-filled  gap  at  the  Whirlpool  belonged  to  the  same  line  (  f  ancient 
erosion  with  the  drift-filled  gap  at  St.  Davids.  •  Their  conclusion 
has  been  generally  accepted  by  subsequent  investigators,  but  the 
interpretation  of  the  phenomena  was  carried  little  farther  until 


1  Travfjls  in  North  Aun-ricii.    By  Cliniies  T,y*-ll.    Xtnv  Yiiik,  !H4n.    Vol.  II,  pp.  77-80. 
>'utural  History  of  New  York.    Ueolony,  I'art  IV.    liy  James  Hall,  pp.  asa-auo. 


urn 


itro 


{     Ku:\: 


m  ^mmm 


h 

e 

h 
•1 

to 

a 


//], 


I 


Commissioners  of  the  State  Reservation  at  Niagara.      75 

the  subjoot  \V!is  studiod  by  Dr.  Jalius  Pohlmiui. '  He  pointed  out 
that  the  upper  course  of  the  ancient  {j;or^e  C(jukl  not  have  lain 
outside  the  modern  ^orj^e.  If  the  course  of  one  ^or^e  hiy  athwart 
the  course  of  the  other,  we  sliouhl  have  two  breaks  in  the  con- 
tinuity of  the  strata,  instead  of  the  sinj^le  one  at  the  Whirlpool. 
The  upper  part  of  the  ancient  gor<j;e  necessarily  coincides  with  a 
part  of  the  modern  f^or^e ;  and  so,  when  the  cataract,  in  the  pro- 
gressive excavation  of  the  canyon,  reached  a  point  at  the  Whirl- 
\)o<^\  where  it  had  no  firm  rock  to  erode,  it  had  only  to  clear  out 
the  inc!ohereut  earth  and  boulders  of  <4;lacial  drift.  To  Avhatever 
distance  the  f:?orge  of  the  earlier  stream  extended,  the  modern 
river  found  its  laborious  task  performed  in  advance. 

Let  us  jmt  to>i;ether  what  we  have  learned  of  the  Niaji;ara  history. 
The  river  b(^i:;an  its  existence  during  the  final  retreat  of  the  great 
ice  sheet,  or,  in  other  words,  durin,!j;  the  series  of  events  that  closed 
the  age  of  ice  in  Nortli  America.  If  we  consider  as  a  geologic 
period  the  entire  time  that  has  elapsed  since  the  beginning  of  the 
age  of  ice,  then  the  history  of  the  Niagara  river  covers  only  a 
portion  of  that  period.  In  the  judgment  of  most  students  of 
glacial  geology,  and,  I  may  add,  in  my  own  judgment,  it  covers  only 
a  small  portion  of  that  period. 

During  the  course  of  its  history,  the  length  of  the  river  has 
sufi:ered  some  variation  by  reason  of  the  successive  fall  and  rise 
of  the  level  of  Lake  Ontario.  It  was  at  first  a  few  miles  shorter 
than  now ;  then  it  became  suddenly  a  few  miles  longer,  and  its 
present  length  was  gradually  acquired. 

With  the  change  in  the  position  of  its  mouth  there  went  a 
change  in  the  height  of  its  mouth ;  and  tlu^  rate  at  which  it  eroded 
its  channel  was  att'ected  thereby.  The  influence  on  the  rate  of 
erosion  was  felt  cliiefiy  along  the  lower  course  of  the  river, 
between  Lewiston  and  Fort  Niagara. 

The  volume  of  the  river  has  likewise  been  inconstant.  In  early 
days,  when  the  lakes  levied  a  large  tribute  on  the  melting  glacier, 
the  Niagara  may  have  been  a  larger  river  than  now ;  but  there 
was  a  time  wlieu  the  discliarge  from  the  upper  lakes  avoided  the 
route  by  Lake  Erie,  and  then  the  Niagara  was  a  relatively  small 
stream. 


1  Proc.  A.  a.  a.  S.,  36tb  MeotiDK  (Buffalo),  pp.  221-222. 


' 


76 


Sixth  Annual  Eei'out  of  the 


The  ^rejit  life  work  of  the  river  has  been  the  dij^j^'in*^  of  the  }^orge 
through  which  it  ruuH  from  tho  Ciitaract  to  Lowistou.  The  bcgiu- 
uiug  of  its  lift'  was  tlif  bcginuiug  of  that  task.  The  length  of  the 
gorge  is  iu  some  sense  a  mc^asure  of  the  river's  ago.  lu  the  main 
the  material  dug  has  IxM'n  hard  limestone  and  sandstone,  inter- 
bedded  with  a  coherent  thoiigh  softer  shale;  but  for  a  part  of  the 
distance  the  material  was  incoherent  drift. 

The  geologic  ago  of  tlu;  earth  — the  time  during  which  its 
surface  has  been  somewhat  as  now,  divided  into  laud  and  ocean, 
subject  to  endless  waste  on  the  land  and  to  endless  accumulation  of 
sediment  iu  the  ocean,  green  with  verdure  and  nourishing  the 
varied  forms  of  animal  life  —  this  time  is  of  immense  duration. 
Even  the  units  into  which  geologists  divide  it,  the  periods  and 
epochs  of  their  chronology,  are  themselves  of  vast  duration. 
Human  history  is  relatively  so  short,  and  its  units  of  (centuries 
and  years  are  so  exceedingly  brief,  that  the  two  orders  of  time  are 
hardly  commensiirate.  Over  and  over  again  the  attempt  has  been 
made  to  link  together  the  two  chronologies,  to  obtain  for  the 
geologic  units  some  satisfactory  expression  in  the  units  of  human 
history.  It  can  not  in  fairness  be  said  that  all  these  attempts  have 
failed,  for  some  of  them  are  novel  and  untested ;  but,  however 
successful  or  unsuccessful  they  may  have  been,  the  interest  in  the 
subject  remains,  and  no  discussion  of  the  history  of  the  Niagara 
river  would  be  complete  without  some  allusion  to  its  value  as  a 
geologic  chronometer.  It  is  true  we  know  but  little  of  the  ratio 
the  river  epoch  bears  to  the  extent  of  the  glacial  period,  or  to  any 
longer  geologic  unit ;  but  yet  were  we  able  to  determine,  even 
approximately,  the  time  consumed  by  the  river  in  cutting  its 
gorge,  we  should  render  less  hazy  and  vague  our  conception  of  the 
order  of  magnitude  of  the  units  of  the  earth's  geologic  history. 
The  problem  has  been  attacked  by  numerous  Avriters,  and  the 
resulting  estimates  have  ranged  from  three  or  four  thousand 
years  to  three  or  four  million  years. 

The  method  of  reaching  a  time  estimate  has  been,  first,  to 
estimate  the  present  rate  of  recession  —  the  rate  at  which  the 
cataract  is  increasing  the  length  of  the  gorge  ;  second,  to  compute, 
with  '".he  aid  of  this  estimate  and  the  known  length  of  the  gorge, 
the  time  necessary  for  the  entire  excavation ;    and,  third,   some 


rorge 

:)f  the 

inaiu 

intor- 

Df  the 


ch  its 
ocean, 
tion  of 
ig  the 
rut  ion. 
As  aud 
ii-atiou. 
uturies 
line  are 
[IS  been 
for  the 
[human 
its  have 
owever 
t  in  the 
Sliagara 
[\\G  as  a 

le  ratio 
to  any 
|e,  even 

ting  its 
111  of  the 

history. 

Iiucl  the 

Lousand 

Itirat,  to 
■lich  the 
[)mpnte, 
gorge, 
ll,  some 


Commissioners  of  the  State  Resekvation  at  Niagara.       77 

writers  have  modified  their  result  by  giving  consideration  to  various 
conditiims  affecting  the  rate  of  erosion  during  earlier  stages  of  the 
excavation.  The  enormous  range  of  the  resulting  estimates  of 
time  has  depended  chiefly  upon  the  imperfection  of  data  with 
reference  to  the  present  rate  of  recession  of  the  falls.  It  is  but 
a  few  years  since  measurement  of  the  rate  of  recession  was 
substituted  for  bald  guessing. 

This  measurement  consists  in  making  surveys  and  maps  of  the 
falls  at  different  times,  so  that  the  amount  of  change  in  the  interval 
between  surveys  can  be  ascertained  by  comparison  of  the  maps. 
In  1842  Professor  Hall  made  a  survey  of  the  outlines  of  the  falls, 
and  he  published,  for  the  use  of  future  investigators,  not  only  the 
map  resulting  from  the  survey,  but  also  the  bearings  taken  with 
the  surveying  instrumont  in  determining  the  principal  points  of 
the  map.'  He  likewise  left  upon  the  ground  a  number  of  well- 
marked  monuments  to  which  future  surveys  could  be  referred. 
Thirty-three  years  later  a  second  survey  was  made  by  the  United 
States  Army  Engineers,  and  they  added  still  further  to  the  series 
of  bench  vc  ks  available  for  future  reference.  Three  years  ago. 
my  colleague,  Mr.  R.  S.  Woodward,  executed  a  third  survey.'* 

Plate  VII  exhibits  the  outline  of  the  crest  of  the  falls,  together 
with  the  brink  of  the  (dilT  in  the  vicinity  of  the  falls,  as  determined 
by  Mr.  Woodward  in  188(),  aud  also  shows  a  ])art  of  the  same  out- 
line as  determined  by  Professor  Hall  forty-four  years  earlier.^  If 
both  were  precise,  the  area  included  between  the  two  lines  would 
exactly  represent  the  recession  of  the  Horseshoe  and  American 
falls  in  forty-four  years,  and  the  retreat  of  the  cliff  face  at  Goat 
Island  in  the  same  time.  I  regret  to  say  that  there  is  internal 
evidence  pointing  to  some  defect  in  one  or  both  surveys,  for  there 
ai'e  some  points  at  which  the  Woodward  outline  projects  farther 
towards  the  gorge  than  the  Hall  outline,  and  yet  we  can  not  believe 
that  any  additions  have  been  made  to  the  face  of  the  cliff.  Never- 
theless, a  critical  study,  not  mersly  of  these  bare  lines  on  the  chart, 
but  also  of  the  fuller  data  in  the  surveyors'  notes,  leads  to  the 
belief  that  the  rate  of  recession  in  the  central  part  of  the  Horse- 


1  Natural  HiBtory  of  New  York,  Goolof?y,  Tart  IV,  pp.  40-2-40;i. 

2  Soionce,  Vol.  VIII,  188C,  p.  205. 

;t  The  poutli  side  of  this  chart  ia  placed  iippomiost  (iu  violation  of  the  conventional 
rule)  so  that  it  may  accord  with  the  bird's-eye  views. 


!  t 


78 


Sixth  Annual  Report  op  the 


shoe  Fall  is  approxiiuutol}'  dotermiuecl,  niitl  tliut.  it  is  Hoiuewhere 
between  four  foet  Jiutl  six  foot  i^er  aniuira.  The  amount  fall«'n 
away  at  the  sides  oi'  the  Horsoshoii  is  not  well  cloteriniued,  but 
this  is  of  less  importance,  for  such  falling;  away  alTects  the  width 
of  the  gorge  rather  than  its  length,  and  it  is  the  length  with  which 
we  are  concerned. 

The  surveys  likewise  fail  to  afford  any  valuable  estimate  of  the 
rate  of  retreat  of  the  American  Fall,  merely  telling  us  that  its  rale 
is  far  less  than  that  of  the  Horseshoe  —  a  result  that  might  be 
reached  independently  by  going  back  in  imagination  to  the  time 
when  the  two  falls  were  togetiier  at  the  foot  of  Goat  Island, 
and  considering  how  much  greater  is  the  distance  through  which 
the  Horseshoe  Fall  has  since  retreated.  The  rate  of  retreat  of  the 
central  portioii  of  the  Horseshoe  is  the  rate  at  which  the  gorge 
grows  loL^;er. 

Now  if  we  were  to  divide  tlu;  entire  length  of  the  gorge  by  the 
space  through  which  the  Horseshoe  Fall  retreats  in  a  yeai",  we 
might  regard  the  resulting  (quotient  as  expressing  the  number  of 
years  that  the  falls  have  been  occupied  with  their  work.  This  is 
precisely  the  procedure  by  which  the  majority  of  time  estimates 
have  been  deduced,  but  in  my  judgment  it  is  not  defensible.  It 
implies  that  the  rate  of  retrogression  has  been  uniform,  or,  more 
precisely,  that  the  present  rate  of  retrogression  does  not  differ 
from  the  averag(^  rate,  and  this  imjjlication  is  open  to  serious 
question,  I  conceive  that  future  progress  in  the  discussion  of  the 
time  problem  will  consist  chiefly  in  determining  in  what  ways  the 
conditions  or  circumstances  that  affect  the  rate  of  retrogression 
have  varied  in  past  time.  In  order  to  discuss  intelligently  these 
conditions,  it  is  necessary  to  understand  just  what  is  the  process 
by  which  the  river  increases  the  length  of  its  gorge. 

There  can  be  no  question  that  the  cataract  is  the  efficient 
engine,  but  what  kind  of  an  engine  is  it  ?  What  is  the  principle 
on  which  it  works  ? 

It  has  already  been  stated  that  the  rocks  at  the  falls  lie  in  level 
layers.  The  order  of  succession  of  the  laycns  has  much  to  do  with 
the  nature  of  the  cataract's  work.  Above  all  is  a  loose  sheet  of  drift, 
but  this  yields  so  readily  to  the  wash  of  the  w'der  that  we  need 
pay  no  attention  to  it  at  present.     Under  that  is  a  bed  of  strong 


I 


me  where 
int  fallen 
iued,  but 
ihe  width 
ith  which 

ite  of  the 
it  its  rale 
iui<^ht  be 
the  time 
t  Ishiud, 
^h  which 
3at  of  the 
he  gorge 

^0  by  the 
year,  we 
imber  of 
This  is 
:isti  mates 
ublo.  It 
or,  more 
lot  difJ'er 
>  serious 
on  of  the 
ways  the 
agression 
tly  these 
i  process 

efficient 
principle 

3  in  level 
3  do  with 
t  of  drift, 
we  need 
)f  strong 


PI.ATE  VII.- Chart  of  the  CUtr  L.nTTt   th.  hen.,   „f  «..    ^,„„„,,  ,,„^.J 
compiled  to  show  the  Recession  from  IHii  to  188G 

^'I'u^r/TnTsr  Ful/irn'e'^rBt'U'f  .r"^'  '^'"^  ""'  '"^^^^O  ^^  ^-  ^-  state  Geol- 


I 


COMMIHHIONEKH   OF  THE   StaTE   RehEHVATION   AT  NiAOARA.  79 


limeHtoiu\  ^riiis  is  cuIIchI  tlio  Niii^'iira  linicstono,  and  its  thickuesa 
is  oi^lity  feet.  IJeiitNith  it  in  u  sluilo,  calh'd  tho  Niagara  shale, 
with  a  thirkneHs  of  fifty  f»M.'t;  ami  then  for  thirty-tivo  feet  there  is 
an  alternation  of  liniestoue,  shale  and  f^andstone,  known  collfetively 
as  the  (Minton  ^ronp.  This  rea(di('s  down  very  nearly  to  the 
water's  edf^o.  Beneath  it,  and  extending*  downward  for  several 
hnndnnl  feet,  is  a  }j;reat  bed  of  soft,  sandy  shale,  interrnpted,  so  far 
as  wo  know,  by  but  a  sinj^le  inird  layer,  a  sandstone  ledf»e,  varying 
in  thickness  from  ten  to  twenty  feet.  These  are  the  Mculiua  shales 
and  the  ^ledina  sandstone.  Th(!  ])r()hl<'  in  Phiti'  VIII  indicates  that 
the  hard  layers  pi'ojiu't  as  shelves  or  steps,  and  th  t  the  softer 
layers  are  eaten  back.  I  have  been  led  so  to  draw  them  by  con- 
siderations of  analojj;y  oidy,  for  underneath  the  center  of  the  great 
cata.ract  no  observations  have  b(>en  mud<i.  We  only  know  that  the 
river  leaps  from  the  upper  surface  of  the  Niagara  limestone  and 
strikes  upon  the  water  of  the  pf)ol.  The  indicated  depth  of  the 
pool,  too,  is  a  mere  surmise,  for  in  that  commotion  of  waters  direct 
observation  is  out  of  the  ([uestion.  ]>ut  where  the  United  States 
Engineers  were  able  to  lower  their  plummet,  a  half  a  mile  away,  a 
depth  was  discovered  of  nearly  200  feet,  and  I  have  assumed  that 
the  cataract  is  scouring  as  deeply  now  as  it  scoured  at  the  time 
when  that  part  of  the  gorge  was  dug. 

It  is  a  matter  of  direct  observation  that,  from  time  to  time,  largo 
blocks  of  the  upper  limestone  fall  away  into  the  pool,  and  there 
seems  no  escape  from  the  inference  that  this  occurs  because  the 
erosion  of  the  shale  ^  ^neath  deprives  the  limestones  of  its  support. 
Just  lunv  the  shale  is  eroded,  and  what  is  the  ])art  played  by  the 
harder  layers  beneath,  are  (juestions  in  regard  to  which  we  are 
much  in  doubt.  In  the  Cave  of  the  Winds,  where  one  can  pass 
b(uieath  and  behind  one  of  the  thinner  segments  of  the  divided 
fall,  the  air  is  tilled  with  spray  and  heavier  masses  of  water  that 
perpetually  dash  against  the  shale,  and  though  their  force  in  that 
place  does  not  seem  to  be  violent,  it  is  possible  tnat  their  con- 
tinual beating  is  the  action  that  removes  the  slialy  rock.  The 
shale  is  of  the  variet}'  known  as  calcareous,  aud  as  its  calcareous 
oleraeut  is  solul)le,  it  may  be  that  solution  plays  its  part  in  the 
work  of  undermining.  What  goes  on  beneath  the  water  of  the  pool 
must  be  essentially  difFereut.     The  Niagara  river  carries  no  sedi- 


UMJI  .V.  U-l 


^/ 


80 


Sixth  Annual  Report  of  the 


ment,  and  therefore  cau  not  scour  its  cliaunel  in  the  manner  of 
most  rivers,  bnt  the  fra<i;meuts  of  the  limestone  bed  that  fall  into  the 
pool  must  bf  moved  by  the  pluu^in^  water,  else  they  would 
accumulate  and  impede  its  work;  and  beinjj;  moved,  we  can  under- 
stand that  they  become  powerful  ajj;ents  of  excavation.  Water 
plunging  into  a  pool  aciiuires  a  gyratory  motion,  and,  carrying 
detritus  about  with  it,  sometimes  bores  deep  holes,  even  in  rocks 
that  are  hard.  These  holes  are  called  technically  "pot-holes,"  and 
there  is  much  to  commend  the  suggestion  that  the  excavation 
within  the  pool  is  essentially  pot-hole  work.' 

The  process  which  I  havo  described  is  that  which  takes  place  in 
the  central  part  of  the  Horseshoe  Fall,  where  the  greatest  body  of 
water  is  precipitated.  At  the  margin  of  the  Horseshoe,  and  also 
at  the  American  Fall,  in  which  places  the  hodj  of  falling  water 
is  much  less,  the  pro(3ess  is  dillerent.  There  is  there  no  pot-hole 
action  and  no  pool.  The  fallen  blocks  of  limestone  form  a  low 
talus  at  the  foot  of  the  cliff,  and  upon  them  the  force  of  the  descend- 
ing water  is  broken  and  spent.  Such  of  you  as  have  made  the 
excursion  througli  the  Cave  of  the  Winds,  will  recall  that  though 
for  a  few  steps  you  traveled  upon  an  undisturbed  rock  stratum, 
one  of  the  layers  of  the  Clinton  i  oup,  the  greater  part  of  the 
journey  Lay  across  large,  fallen  blocks  of  limei-itone,  irregidarly 
heaped.  Where,  then,  the  volume  of  fallhig  water  is  relatively 
small,  the  great  bed  of  shale  below  the  Clinton  ledges  plays  no 
part,  and  the  rate  at  which  the  limestone  breaks  away  is  deter- 
mined purely  by  the  rate  of  erosion  of  the  shale  bed  lying  just 
beneath  it. 

The  difference  between  the  two  processes  is  of  great  im])ortance 
in  the  present  connection,  because  the  two  rates  of  erosion  are 
very  different. 

I  am  fully  aware  that  this  sketch  of  the  cataract's  work  is  not  a 
satisfactory  explanation  of  the  mode  of  recession,  but  it  yet  serves 
a  present  purpose,  for  it  renders  it  possible  to  point  out  that  the 
rate  of  recession  is  affected  by  certain  factors  which  may  have 
varied  during  the  earlier  history  of  the  river.  We  see  that  the 
process  of  recession  is  concerned  with  a  heavy  bed  of  hard  rock 


1  I  am  Indobtod  for  this  su-^  'ostlon  to  Mr.  W.  J.  McGeo. 


h 


manner  of 
11  into  the 
ey  would 
!an  under- 
1.  Water 
,  carrying 
Q  in  rocks 
olea,"  and 
xcavation 

s  place  in 
it  body  of 

and  also 
iug  water 
'  pot-hole 
rm  a  low 
)  descend- 
niade  the 
Lt  though 

stratum, 
brt  of  the 
■regularly 
relatively 
plays  no 
'  is  deter- 
ying  just 

iportance 
osion  are 

k  is  not  a 
^et  serves 

that  the 
oay  have 

that  the 
ard  rock 


i 


III- 


\  1 


a: 
> 


ij 

z 
o 
I- 
co 
u 

2 


< 
< 
< 


mm 
I  if  ' 


u 

_l 

< 

I 


< 

ir 

< 
< 


z 
o 

a: 
o 
u. 


z 
o 

H 

z 
J 
O 


I'l'liUil.lilil.Mli 


< 

Z 

5 
111 

2 


z 
o 

s 
c 
o 


8 
o 

it 

I 


0< 


•jg 


-'I;  |ii|  1 iinmir^miimnifir 


/ 


, 


/ 


Commissioners  of  the  State  Reservation  at  Niagara.       81 

above,  with  beds  of  softer  rock  beneath,  with  the  foice  of  falling 
water,  and  possibly,  also,  with  the  solvent  power  of  the  water. 

Concerning  each  of  these  factors  a  number  of  pertinent  questions 
may  be  asked,  questions  that  should  certainly  be  considered, 
whether  they  are  answered  or  not,  before  any  solution  of  the  time 
problem  is  regarded  as  satisfactory.  To  illustrat(!  their  pertinence, 
a  few  will  be  propounded. 

Question  1.  Does  the  limestone  vary  in  constitution  in  different 
parts  of  the  gorge  ?  If  its  texture  or  its  system  of  cracks  and 
joints  varies,  the  process  of  recession  may  vary  in  consequence. 

Question  2.  How  does  the  limestone  bed  vary  in  thickness  in 
different  parts  of  the  gorge  V  This  question  is  easily  answered, 
for  at  all  points  it  is  well  exposed  for  measurement. 

Question  3.  How  is  the  thickness  of  the  limestone  related  to  the 
rate  of  recession?  This  is  more  difficult.  The  dobris  from  a 
very  thick  bed  of  limestone  would  oppose  great  resistance  to  the 
cataract  and  check  its  work,  The  di'bris  from  a  very  tliin  bed 
would  afford  small  and  inefficient  pestles  for  pot-hole  action,  and 
might  lead  to  a  slow  rate  of  recession.  If  the  thickness  now  seen 
at  the  cataract  Avere  slightly  increased  or  slightly  diminished,  it  is 
not  at  once  apparent  how  the  rate  of  recession  wouhl  be  affected, 
and  yet  there  might  be  an  important  difference. 

We  have  seen  that  the  pre-glacial  stream  whoso  channel  is 
betrayed  at  the  Whirlpool,  removed  the  Niagara  liinestone  through 
a  portion  of  the  gorge,  and 

Question  4  asks  :  Through  what  portion  of  the  gorge  was  the 
Niagara  limestone  absent  when  the  Niagara  river  began  its  Avork  ? 

Questions.  Does  the  rock  section  beneath  the  limestoiio  —  the 
shale  series  Avitli  its  imbedded  harder  lavers  —  does  this  vary  in 
different  parts  of  the  gorge  V 

Question  (>.  Through  wJiat  distance  Avere  the  several  members 
of  the  underlying  rock  series  removed  by  the  action  of  the 
pre-glacial  stream  ? 

Coming  noAv  to  consider  the  force  of  the  falling  Avater,  a  little 
consideration  serves  to  sIioav  that  the  force  depends  on  at  least 
three  things  :  The  height  through  Avbich  the  Avater  falls,  the  degree 
of  concentration  of  the  stream,  and  the  volume  of  the  river. 


L«^ 


82 


Sixth  Annual  Report  of  the 


Tlio  height  of  tlio  fall  is  tlio  vortical  distance  from  its  crest  to 
the  surface  of  the  pool  below. 

Question  7  asks  :  How  has  the  hei}j;ht  of  the  crest  of  the  fall 
varied  diirin*^  the  history  of  recession '? 

Question  8.  How  has  the  height  of  the  base  of  the  fall  varied  ? 
And  this  involves  a  subsidiary  question, —  to  what  extent  has  the 
excavated  gorge,  as  left  by  the  retreating  cataract,  been  refilled, 
either  by  the  falling  in  of  fragments  from  the  clifts,  or  by 
contributions  of  debris  brought  by  the  current? 

Question  9.  What  has  been  the  form  of  the  channel  at  the  crest 
of  the  fall,  from  point  to  point,  during  the  recession?  Wherever 
the  channel  has  been  broad,  and  the  water  of  uniform  depth  from 
side  to  side,  the  force  of  the  falling  water  has  been  applied  dis- 
advantageously ;  wherever  the  channel  has  been  narrow,  or  has 
been  much  deeper  in  some  parts  than  in  others,  the  force  of  the 
water  has  been  a])plied  advantageously. 

There  are  many  ways  in  which  it  is  possible  that  the  volume 
of  the  river  was  made  to  differ  at  early  dates  from  its  present 
volume.  During  the  presence  f)f  the  ice,  there  was  a  different 
climate,  and  there  were  different  drainage  systems. 

Question  10.  During  the  early  history  of  the  river,  was  the 
annual  rainfall  cm  which  its  water  su})ply  depended  greater  or 
less  than  now  ? 

Question  11.  Was  the  evaporation  from  the  basin  at  that  time 
greater  or  less  than  now  ?  It  is  believed  that  at  the  present  time 
the  Niagara  river  receives  less  than  half  the  water  that  falls  upon 
its  basin  in  rain  and  snow,  the  remainder  being  returned  to  the  air 
by  evaporation  from  the  lakes,  from  the  surface  of  the  land  and 
from  vegetation. 

Question  12.  Was  the  water  su})ply  increased  by  ablation? 
There  may  have  been  times  Avhen  the  overla])ping  edge  of  the 
glacier  discharged  to  the  Laurentian  basin  large  bodies  of  water 
furnished  by  the  molting  of  ice  that  had  congealed  from  the  clouds 
of  regions  far  away. 

Question  113.  Was  the  drainage  area  of  the  river  at  any  time 
increased  through  the  agency  of  ice  barriers  ?  Just  as  the  W^innipeg 
basin  was  made  to  send  its  water  to  the  Mississippi,  sf)  we  can 
imagine  that  regions  north  of  the  Great  Lakes  and  now  tributary 


I  , 


il 


».«-• 


lie 


fall 


! 


Commissioners  of  the  State  Eeservation  at  Niagara.      8B 

to  Hudson's  bay,  had  tlioir  disoliavge  temporarily  turued  to  Lake 
Superior  and  Lake  Huron. 

On  the  other  hand,  we  have  seen  that  the  discharge  of  the  whole 
district  of  the  u])per  lakes  was  for  a  time  turned  away  from  the 
Niagara  river.     Therefore,  we  ask  : 

Question  14  To  what  extent  and  for  what  periods  was  the 
volume  of  the  river  diminished  through  the  diversion  of  the 
discharge  of  the  upper  lakes  ? 

Assuming  all  these  questions  to  be  answered  one  by  one,  and 
the  variations  of  different  sorts  determined,  it  is  still  necessary 
to  learn  the  relations  of  those  variations  to  each  other,  and  so 
we  ask  : 

Question  15.  How  have  the  variations  of  rock  section,  the 
variations  of  cataract  height,  the  variations  of  form  of  channel  and 
the  variations  of  volume  been  related  to  one  another  in  point  of 
time?     What  have  been  their  actual  combinations? 

Question  16.  How  have  the  various  temporar}'  combinations  of 
factors  affected  the  process  of  retreat  and  the  rate  of  recession. 

The  tale  of  questions  is  not  exhausted,  but  no  more  are  needed 
if  only  it  has  been  shown  that  the  subject  is  not  in  reality  simple, 
as  many  have  assumed,  but  highly  complex.  Some  of  the  ques- 
tions are,  indeed,  easily  ansAvered.  It  may  be  possible  to  show 
that  others  are  of  small  moment.  It  may  even  be  that  careful 
study  of  the  local  features  will  enable  the  investigator  to  infer  the 
process  of  cataract  work  at  each  point  from  the  existing  condition 
of  the  gorge,  and  thus  relieve  him  from  the  necessity  of  considering 
such  remote  (Questions  as  the  nature  of  glacial  climate  and  the 
history  of  glacial  retreat.  But  aftiM'  all  ])ariug  and  pruning  what 
remains  of  the  problem  will  be  no  bagatelle.  It  is  not  to  be  solved 
by  a  few  figures  on  a  slate,  nor  yet  by  the  writing  of  many  essays. 
It  is  not  to  be  solved  by  the  cunning  discussion  of  our  scant,  yet 
too  puzzling  knowledge  —  smoothing  away  inconvenient  doubts  with 
convenient  assumptions,  and  cancelling  out,  as  though  compen- 
satory, terms  of  unknown  value  that  happen  to  stand  on  oj)posite 
sides  of  the  eipiation.  It  is  a  problem  of  nature,  and  like  other 
natural  prol)lenis  demands  the  patient  gathering  of  many  facts,  of 
f:i3ts  of  many  kinds,  of  categories  of  facts  suggested  by  the  ten- 


K*"^ 


i&a 


H 


ii  i 


84   Sixth  Annual  Report  on  State  Reservation  at  Niagara. 

tative  theories  of  to-day,  and  of  new  categories  of  facts  to  be 
suggested  hy  new  theories. 

I  have  said  our  problem  is  but  the  stepping  stone  to  another 
problem,  tli(!  discovery  of  common  units  for  earth  history  and 
human  history.  The  Niagara  bridges  the  cliasm  in  another  way, 
or  more  strictly,  in  another  sense,  for  the  term  of  its  life  belongs 
to  both  histories.  The  river  sprang  from  a  great  geologic  revolu- 
tion, the  banishment  of  the  dynasty  of  cold,  and  so  its  lifetime  is  a 
geologic  epoch  ;  but  from  first  to  last  man  has  been  the  witness  of 
its  toil,  and  so  its  history  is  interwoven  with  the  history  of  man. 
The  human  comrade  of  the  river's  youth  was  not,  alas,  a  reporter 
with  a  '^  ^te-book,  else  our  present  labor  would  be  light.  He  has 
even  told  us  little  of  himself.  We  only  know  that  on  a  gravelly 
beach  of  Lake  Irocpiois,  now  the  Ridge  road,  he  rudely  gathered 
stones  to  make  a  hearth,  and  built  a  fire  ;  and  the  next  storm 
breakers,  forcing  back  the  beach,  buried  and  thus  preserved,  to 
gratify  yet  whet  our  curiosity,  hearth,  ashes  and  charred  sticks. ' 

In  these  Darwinian  days,  we  can  not  deem  primeval  the  man 
possessed  of  the  Promethean  art  of  fire,  and  so  his  presence  on 
the  scene  adds  zest  to  the  pursuit  of  the  Niagara  problem.  What- 
ever the  antiquity  of  the  great  cataract  may  be  found  to  be,  the 
antiquity  of  man  is  greater. 

1  American  AnthropoloRist,  Vol.  II,  pp.  173-174. 


^1  * 


Y 


